A traffic garda has been suspended from duty following a claim by a south Dublin builder that he was asked for a £20,000 bribe to have a drunk-driving charge dropped.
Detectives have seized records from a south Dublin Garda station as part of an investigation into the claims.
The station's traffic unit has been temporarily closed while the investigation. is under way.
Senior detectives have been seconded to the investigation, which began after a complaint by the builder that he had been approached for a bribe.
One uniformed garda has been suspended and four plainclothes detectives questioned.
The claim by the builder arises from an incident in May 1999 in which he was stopped by uniformed gardai in the south of the city.
The man has claimed that a garda subsequently approached him three days before Christmas and asked him for £20,000 in return for which the charge would be dropped.
The builder made a complaint to the Garda authorities. An investigation was started under the National Bureau for Criminal Investigation (NBCI) and the garda was arrested last week. He has been suspended from duty.
The NBCI investigators also questioned detectives from a south Dublin station about contact they had with traffic gardai about the same drunk-driving case at around the time the builder was arrested in 1999.
It is understood another uniformed garda has said he was approached by local detectives about the initial drunken-driving arrest.
However, it is understood the local detectives were not questioned about bribery or any other serious offences.